Rivets are, of course, a well known and popular form of fastener because of their simplicity, dependability and low cost. There are many different types of rivets and many methods of applying the rivets to the materials to be joined. For example, where access is provided on both sides of the elements to be joined, a projecting end of a rivet can be repeatedly impacted while the opposite end is held in place by a bucking bar. Thus, the rivet material is displaced laterally outwardly and into contact with the side of the hole in which it is being assembled. Similarly, rivets can be squeezed into place by applying steady pressure on a header die while backing up the preformed end of the rivet with a bucking bar or holding fixture. Rivets are also provided with hollow ends or prongs. In these rivets, the prongs are bent back against the material being fastened whereby the elements joined by the riveting action are held between the rivet head and the laterally outwardly bent prongs or tubular portions of the rivet. These rivets are not particularly useful for blind holes nor do they provide high tensile strength, as most afford strength only in shear.